Shaft seal and pressure plate therefor



Aug. 19, 1952 M. KATCHER 2,607,615

' SHAFT SEAL AND PRESSURE PLATE THEREFOR Filed March 20, 1948 INVENTORKara/ 5e,

ATTORNEY consists of an outer rim 25, with its forward face concaved,that is its face away from washer l2. Extending radially inward from rim25 and to a certain extent axially forward, is a slit web 26. Theslitting of web 26 gives rise to a plurality of resilient spokesextending radially inward. Compressed between the forward face of rim25. and impeller I is a spring 22. This forces rim 25 rear wardlyagainst bulb portion I5, forcing the latter against sealing washer I2which in turn is pressed against the forward end of hub 9. Water is thusprevented from passing from the pump between the end of hub 9 andsealing washer I2 and between bulb portion I6 and washer I2.

As seen in Fig. 3 in dotted lines, web 26 normally extends axiallyforward a less distance than the axial distance between the forward edgeof bulb l6 and the forward edge of head I of rubber ring I I. Therefore,when spring 22 forces rim 25 back against bulb I6, web 26 is bentagainst itsresilience causing it to exert spring pressure 'on theforward leg of head. I5. This results in forcing .portion I5 downwardlyagainst'shaft 3 Fig. 4, the radially inner end of the slit or spoked webof pressure plate I8 is replaced with a ring plate 28. In a broad sense,plate 28 can be considered as the radially inner end of the modi fledweb. Spokes 29, extending between radially inner ring plate 28 andradially outer ring plate 21, are flexible so that when ring plate 21 isforced against bulb I6 by spring .22, ring Plate 28 will bear againstthe forward leg of portion I5. The

V necessary stiffness forit to press rearward against portion I5 toeffect theylatters scaling function,

. yet it must be flexible enough to allow rim 25to and forwardly againstwasher or sealing ring I2 1 for maintaining portion I5 in sealingrelationv with the washer and the washer in turn in sealing relationwith the inner end of hub 9. It will be noted that web 26 engages theforward leg of portion I5 at an angle so as to force it in bothdirections to. maintain a seal between both shaft,

, 3-and sealing washer I2.

. of said forward leg of portion I5 on shaft 3 inter- However, thebinding feres to a certain extent with its efiiciency in bear- 7 ing atits rearward end, that is adjacent washer I2, leaving the bearing at thelatter location to take place largely through the yielding of the rubberof which portion I5 is formed. Sealing washer I2 is provided with abeveled recess 24 adjacent shaft 3, the rearward end or leg of por--tion I 5-having a complementary bevel to fit therein, so that whateveraxial pressure is transmitted 7 to said rearward end will also cause abinding of said end on the shaft, in addition to a pressure seal withwasher I2, Portion I5 is hollowed out or internally annularly groovedbetween its rear and forward ends to leave a space 25 which is filledwith water grease. The pressure on shaft 3 of the legs of portion I5together with the water grease in space 2!] acts to keep water from thepump .from traveling along the shaft and reaching the bearing (notshown) inside of hub 9. The water grease will tend to permit portion I5to slip along the shaft to allow the axial pressure from web 26 to betransmitted directly to washer I2 Because of the annular groove or space20, each part or leg of portion I5 can be wedged against the shaft to acertain extent independentlyof the other. Any binding on shaft 3 ofportion l5 interferes with the pressure of ring II against sealingwasher I2. As it is desired to get a tight seal between ring II andsealing washer I2 and between washer I2 and the forward end of. hub 9,without interference from the binding noted above, the flange havingbulb portion ISIandnecked down portion I1 is provided, saidfiangebearingaxially only againstwasher I2 .as explained above for the actionof rim 25. This prevents water from passing from the pump between theend of hub 9 and sealing washer I2 and between bulb portion I6 andWasher I2.

Space 21- between bulb portion I6 and'inner portion I5 can also befilled with water grease to assist in the sealing actionbetween ring IIand sealing washer I2.

In the modified form of pressure plate shown in I intended tobebroadenough to cover other matemove back to press sufficiently againstbulb I6forthelatters sealing function.-

The termirubber as used in the is rials of like characteristics such assynthetic rubber. 1

In the particular embodiments illustrated, the

. inner part of the web is normally set, forward a substantial distanceaxially from the, rim, that is, when the web is unsprung, its inner partis at a substantial axial distance forward of the rim.

It will bereadily understood that this distance may be decreased orincreased depending on the .,,:xibility and resilienceof the web andtherelai e axial locations of the inner and outer'portions of the'ring.

Iclaimr. I. 1. For use in a'fluid seal with a rubber vring having aradially outer portion and a radially inner portion at a substantialdistanceradially inward'and axially forward from said outer portion,said portions requiring individual pressure against themv to effect theseal, a spring for furnishing said pressuraa. pressure plate having arim and a flexible resilientweb, said plate being suitablyforrmed withrespect to the rubber ring that its rim is on line axially with saidouter portion, and normally to have its web engage said inner portionwith its rim out'of contact with said outer portion, the rim whenpressed by the spring being moved against its resilience axiallyrearward into contact with said outer portion with sealing pressure, theweb being stiff enough, when the rim is so forced; to exert sealingpressure against said innerportion, the

- form of the p a'then relatively to t r being such that between theplace of. contact of the rim and the ring and the place of contact ofthe web and the ring, the plate is out'of contact with the ring.

2.. For usein a fluid sealwith a rubber ring having a radiallyouterportion and a radially inner portion at, a substantial distance radiallyinward and axially forward from said outer portion, said portionsrequiring individualpressure against them tofeffect the seal,v a spring,for furnishing said pressure, and a pressure plate having a 'rim and a:flexibleresillent web, the

rim being on a line axially with saidiouter portion, and the web havingits inner part on a line axially. with said inner portion, the rimbefore being engaged by the spring being offset axially its bearinghousing, said seal having a sealing washer with one face adjacent thehousing, a rubber ring encircling the shaft adjacent the other face ofthe washer, said ring having a radially inner portion and a radiallyouter portion at a substantial distance radially and axially from theinner portion. a spring, and a pressure plate comprising a rim and aweb, the rim being axially in line with said outer portion and the Webhaving its radially inner part axially in line with said inner portion,the spring bearing against the rim on its opposite face from the ringand forcing it into contact with the outer portion of the ring, theplace of contact of the spring with the rim being in substantially axialalignment with the place of contact of the rim and said outer portion,said plate, before being acted upon by the spring, being formedrelatively to the ring to have its rim out of contact with the outerportion of the ring when the inner part of the webis set against theinner portion of the ring, the web being flexible enough topermit therim to be forced by the spring axially into contact with said outerportion with sealing pressure at the same time the inner part of thewebcontacts said inner portion, the web being stiff enough when the rimis so forced to exert sealing pressure itself against said innerportion.

MORRIS KATCHER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,914,759 Schwitzer et al. June20, 1933 2,225,758 Stein Dec. 2 1, 1940 2,430,426 Katcher Nov. 4, 1947

